Movable bridge



Jan. 4, 1927'. 1,613,485

R. E. sHEAl.

MovABLE BRIDGE :Fi1edsept- 10, 1924 2 sheets-sneer a R. E. SHEAL MOVABLE BRIDGE Jan. 4, 1927.

2 Sheets-Sheet 2 Filed Sept. l0. 192.4

Patented Jan. 4, 1927.

UnirEnfsrATEs Partnr ernten. N

t ROBERT'E. sHEAL, or CLEVELAND, omo.

MOVABLE BRIDGE.

irppiiaaoa filed september 1o, i924. sei-nino. 73eme. Y

rIhis invention rela-tesl to movable bridge structures such 4as those used for handlingV and transporting bullrmaterigal, .examples ot which are stocking bridgesunloadingma5 chinery, and the like.'` These devices are generally of very great size and weight, and frequently, particularly ore bridges and stocking bridges, project to avery considerable height and exhibit a very large `surface to the` wind as wellasbeing generally situated on docks and in other exposed positions where the full torce ofthe wind` isdeveloped.

The objects ot" my invention are the pro-- vision of improved mechanism orpropelling such structures alongtheir-` runways when desiredand at other times lockingtlie saine against any possible movement as a .result of wind pressure; the provision of apiopelling and securing unit applicable to structures of diverse designs, either already existing or.

hereafter erected accordingito the plans or different designers; the provision ot a racl` drive consisting of a. unit mechanism applicable to structures not originally designed therefor; the provision Ofmechanisniotl the characterl described` `which, shall be.;V inaintained in operativerelation witlithe driving rack inorefaccurately than other devices;

whileifurther objects and advantagesof the invention w-ill become apparent as the de-` scription proceeds,`

Inthe drawings accompanying and forining a partl cgttliis application I have illus# trated certain physicalforms inavliicli my inventive idea.V canbe embodied although itA willV be f understood that these drawings are intended merely to illustrate thfegprinciples ot my invention and notato restrict me tot-he details of construction. -Fig. l isan endelevatioii of at-ypical stoclringfbridge equipped with myimprovements; Fig.` 2 is a-plan viewof the driving mechanism, the housing being shown in section; Fig. 3 is a right hand elevation. ofthe mechanism shown in Fig.1f2,the housing being.` likewise shown` in: section;` Fig., iigisfaf` left;v hand elevation o'lil the mechanism, the housing being shown in section; Figs.5 and 6 aresectional views corresponding to the lines A5 5 and` 6-6jrespectively of` Figs. Zand 3 `and looking in the direction ot the arrows; and Fig. 7; is a detail view corresponding tothe line 7 7? ofiFig,3. Movable structures ofthe` type herein `described generally comprise a truss or body Vindependent of the number.

vportion l"supportedy at its ends upon upright towers indicatedfgenerally at 2,.each

tower being suppoittedby means ot' a large number of suit-able wheels 3 3 on a suitable runway. The truss. or body portion oi" the' bridgemay be of any length and design, beinghere shown merely in end elevation; the towers may comprise either a single panel or a plurality of panels or legs; and

any suitableV type ot' wheels and runways may, be eniployechthat here showncoinprising ianged `wheels ruiming on` standard T railsl fastened to cross ties 5. Each leg or panel otsuch tower ordinarily terminates at its lower end in a pair of spaced. lhorizontal sill girders 6-6 formed with suitable prov yvisions indicated at 7-7 in Fig.6 for the reception of the bearings for the supporting wheels. ,Owing to the great weight ot the structures,l it is quite common tofind as manyY 'T il asvthirtyftwo such .wheels located beneath a single leg, although my improvements are My inventionl comprehends a driving de- 16`f16engaging therunway. In this ein bodimentthe wheels 16-16 run, on the same' rails agwhich supportvthe carrying wheels 3. The wheels 3 are located between the girder 6,:6, with their bearings at the outside ofthe wheels as customary in "railroad trucks (see Figi 6) and in my -unit the frame 10 is preferably locatedf Abetween the; wheels 16-16, thus enabling easy yattachment ot the frame to; the girders while permitting its` own wheels;to runupon the` same tracks, thereby automatically;.adjusting thel height thereof above the raclr-17 which `is mountedfon the runway preferably between the rails 4 4. rIhe lower-edges of the members lO-lOare arranged to clear the axles of the carrying wheels as shown in Fig. 3;' The free ends of the girders 6 are preferably stiitened by iio p rectly thereto.

' is generally very massive, the pinion 22 herein illustrated being approximately five feet in suitable bearings 24 and carrying a driving gear 25 meshing with the'pinion anda driven gear 26. I have found it very satisfactory to make the gear 25 in the form of a shrouded gear and fasten the gear 26 dias meshing with a smaller pinion 27 sleeved on a horizontal bar 2S clamped in suitable supports 29, this gear being operatively connected to a Worm gear 30. In the present embodiment I have shown the pinion 27 as formed integral with a sleeve 31 to which the gear is tightlykeyed, thus increasing the strength of the mechanism.

Mounted beneath the Worm gear 30, longitudinally of the frame-is a Worm shaft 32, here shown as provided intermediate its length With a flexible couplingV 3S, one end being journaled in a bearing 34 and the other `end being supported in the bottom section 35 of the gear casing, here shown Vas held in place by a cross member '36 carried by the sills 10-10. One endof this Worm shaft is provided with a Worm 37 meshing With the Worm-gear 30 and the other end With a spur-gear 38 meshing Witha companion gear 3Q carried on the armature shaft of an electric motor 40. This motor is mounted longitudinally of the frame and carried by the cross pieces 13 and 14. The gears 38, 39 have the advantages of `permitting a certain amount of flexibility in the alignment, compensating fori-the speeds of different motors or different current conditions, andv of per- Vmitting the ready `unshipping of the motor for'purposes of repair. While size is not an essential part of the inventionthe mechanism in diameter, and a 100 h. p.V motor being employed. The rack is of similar massive constructionY in this embodiment comprising steel cross pins four inches in diameter and eighteen inches long, and steel side members tivo inches thick and nine inches high. ThisV rack can be anchored to the runway in any desiredmanner, but preferably in the manner described and claimedin my Patent No. 1,435,341, issued November 14, 1922.

F or stopping the operation-of the mechanism and holding `thestructure against accidental movement I have shown a brake drum 42 carried by the end ofthe Worm shaft and provided with suitable brake I have shown the gear 26' shoes 43-43 released by a solenoid 44 through the agency of a brake lever 45, and set automatically by Weights or springs when the current is cut off. The setting action is retarded by a dash pot 46 connected to the brake lever by a compound lever 47. In practice the Weight to set the brake is largely furnished by the lever and solenoid plunger, and associated parts.

The entire mechanism is preferably sheltered in a metal housing comprising vertical sides 50, 51 and a slant top 52, suitablyremovable panels 53 being provided to afford access to the mechanism.

One rack and one unit is employed in connection with each runway. Themotors'are of a reversible type and are often controlled from a distance. The brakes arenormally held in tightcontact with the brake drum by means of springs or levers as described above so that the friction produced thereby, coupled with the high mechanical advantage of the Worm drive, may hold the structure against even the most sever Wind pressure. The solenoid 44 is connected in series with the motor circuit in such Wise that upon starting the motor the brakes will be automatically released and upon turning off the current fromv the motor the brakes Will be automatically reset. The armature shaft is preferably provided With a ily Wheel 48 to prevent the stoppage of the mechanism with such abruptness 'as to injure the moving structure. v

It will be understood that a great many changes in point of detail, construction, design, and arrangement of parts can be made Within the scope of my invention. I do not limit myself to the location of my improved unit at the ends'of the girders; I do not limit its location to a point between the carrying tracks as it can be located between-adjacent pairs of tracks Where the same are not too far separated, 'or' along side a single track in thel caseof certain unloading machinery. I do not limit myself to forming the rack fully independent ofthe carrying rails nor infany other Way `except as specilically recited in my several claims which I desire may be construed each Without reference to limitations contained inother claims.-

Having thus described my invention what I claim is:

1. The Combination with a movable structure having a tower and a truss, of supporting Wheels carried by said tower, a runway for said wheels, a rack along said runway, and a propelling and securingunitv structurally independent of said tower and op-` eratively securedthereto, said unit'comprising a pinion meshing with said rack and an irreversible driving mechanism for said pinion, said mechanism including a Worm gear.

2. The combination with `a movable struc- Vture 'having a tower and a truss, of supportiso y ing wheels carried by said tower, a runway ior said wheels, a rack along said runway, and a propelling and securing unit structurally independent of said tower and operatively secured thereto, said unit comprising a pinion meshing with said rack driving mechaniffm 'for said pinion, including a worm gear, and braking mechanism on the worm aide ot said driving mechanism.

3. The combination with a movable bridge tower et the type having a pair of spaced parallel sill girders, supporting wheels beneath said girders and a runway for said wheels, of a rac-k along said runway, anda trame projecting between said girders and pivoted thereto, said traine having supporting wheels engaging said runwayand a )inion enOaOinO' said rack and mechanismv D D b for driving and restraining said pinion, said mechanism comprising an irreversible worm drive and a fly wheel.

4. The combination with a movable bridg tower of the type having a pair of spaced parallel sill girders, supporting wheels beneath said girders and a runway for said wheels, ot a rack along .said runway, and a frame located beyond said wheels and projecting between Said girders and coupled thereto, supporting wheels carried by that portion of said trame which projects beyond said girders, said last named wheels engaging said runway, a pinion journaled to said traine and engaing said rack, and means Aarried by said Ytrame for starting and Stopping and controlling said pinion.

ln testimony whereof, l hereunto aiiix my signature ROBERT SHEAL. 

